31 



found that the crops are perhaps less likely to be iujiired by early frosts, 

 and a larger variety of productions may be depended u[)on. In fact, all 

 our ordinary garden-vegetables grow on the banks of tliese streams. 



Despite all that has been said of the general iniiutritious qualities of 

 sedges as a forage, the stock in the San Luis Valley thrives the year 

 around on them. There, over thousands of acres, these plants grow 

 more than four feet high. 



Irrigation is possible anywhere in this first division, and water (slightly 

 brackish) is usually obtained by digging a few feet. 



The second division is made up of the higher ground, beyond reach of 

 irrigation. The soil and its productions undergo a complete change. 

 Gramma-grass, chico, and greasevvood are here the prevailing growth. 

 Tlie soil is unpromising in appearance, yet would, if irrigation were pos- 

 sible, produce fair crops. It will not be likely to be brought under the 

 domain of agriculture for many years. Most propitious seasons are, in 

 the absence of water, absolutely required for this kind of soil. It is, 

 however, the legitimate sheep-walk of the valley. 



The third division are the sand-wastes, where there is no water and 

 almost no vegetation. Even the ehico and sage-brash are barely able 

 to live there. 1 know of no use to which it can be put. There are some 

 sheep occasionally foxmd on it, but they derive most of their subsistence 

 from the adjacent vega^ or lowland. 



It is known, also, that in the smaller valleys between spurs of the 

 mountaius, bunch-grass is found in considerable quantity. The pifion- 

 groves furnish shelter and a certain amountof gramma-grass during the 

 winter for the herds that frequent them. 



From Loma, south, wheat has long been a regular crop. Corn, too, 

 produces small ears with certainty at Conejos. It is not unlikely that 

 they could be increased in size by the introduction and thorough accli- 

 mation of better seed, 



I have received the following letter from a reliable and accomplished 

 resident of Colorado, which is important, and probably as much in 

 place here as in any other portion of the report. 



Yours of the 9tli of March is received, and I wouhl hereby ask leave to correct a 

 statemeut made iu the report which I sent you, viz, the estiuiate of the area available 

 for agricultural purposes lu Colorado. That estimate was made upon the geuerally 

 prevailing idea that only the valleys adjacent to the streams of water coukl be culti- 

 vated. A much more scientific and careful estimate has since been made by a calcu- 

 lation of the amount of water anuuaUy discharged through our uu>untain-streanis and 

 the amount required per acre for thorough irrigation, showing that about 7,000,000 

 acres may be cultivated by properly usiug all the water from the streams. Should 

 artesian wells be successfully opened, the agricultural land would be increased, as it is 

 not landj but tvater, which puts the limit upon our available agricultural resources. 



Respectfully, 



L. A. Phillips. 



Emimerafion of plants collected in Central Colorado by Prof. John Wolf 

 during the field-season of 1873, and under the auspices of the Wheeler 

 explorDig expeditiouy party No. 2] Lieut. William L. Marshall in coyn- 



mand. 



EANANCULACE.^. 



CiiEMATiS DouGLASii, Hook, Banks of Clear Creek. June- (92.) 

 C. LiGUSTiciFOLiA, Nutt Valley of the Upper Arkansas. September. 



(89.) 



0- LiausTiciFOLiA, l!irutt., var. with smaller, more toothed leaves, which 



>^- 



